X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;ds=sidebyside;f=block%2Fll_rw_blk.c;h=0603ab2f3692283f7fbeee2ef88a7ebb0bba9864;hb=31f4fde38c5027ca05941db4a05c163d6314278e;hp=1755c053fd68ce648ba90bcbc3c7132ac23d8ad1;hpb=9707b27100a48950f1e15e08a7c5028786e47f55;p=powerpc.git

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 1755c053fd..0603ab2f36 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -638,7 +638,7 @@ void blk_queue_bounce_limit(request_queue_t *q, u64 dma_addr)
 	/* Assume anything <= 4GB can be handled by IOMMU.
 	   Actually some IOMMUs can handle everything, but I don't
 	   know of a way to test this here. */
-	if (bounce_pfn < (0xffffffff>>PAGE_SHIFT))
+	if (bounce_pfn < (min_t(u64,0xffffffff,BLK_BOUNCE_HIGH) >> PAGE_SHIFT))
 		dma = 1;
 	q->bounce_pfn = max_low_pfn;
 #else
@@ -1663,6 +1663,8 @@ static void blk_unplug_timeout(unsigned long data)
  **/
 void blk_start_queue(request_queue_t *q)
 {
+	WARN_ON(!irqs_disabled());
+
 	clear_bit(QUEUE_FLAG_STOPPED, &q->queue_flags);
 
 	/*
@@ -1732,8 +1734,21 @@ void blk_run_queue(struct request_queue *q)
 
 	spin_lock_irqsave(q->queue_lock, flags);
 	blk_remove_plug(q);
-	if (!elv_queue_empty(q))
-		q->request_fn(q);
+
+	/*
+	 * Only recurse once to avoid overrunning the stack, let the unplug
+	 * handling reinvoke the handler shortly if we already got there.
+	 */
+	if (!elv_queue_empty(q)) {
+		if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+			q->request_fn(q);
+			clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags);
+		} else {
+			blk_plug_device(q);
+			kblockd_schedule_work(&q->unplug_work);
+		}
+	}
+
 	spin_unlock_irqrestore(q->queue_lock, flags);
 }
 EXPORT_SYMBOL(blk_run_queue);
@@ -1865,7 +1880,8 @@ EXPORT_SYMBOL(blk_alloc_queue_node);
  *    get dealt with eventually.
  *
  *    The queue spin lock must be held while manipulating the requests on the
- *    request queue.
+ *    request queue; this lock will be taken also from interrupt context, so irq
+ *    disabling is needed for it.
  *
  *    Function returns a pointer to the initialized request queue, or NULL if
  *    it didn't succeed.
@@ -2811,6 +2827,9 @@ static void init_request_from_bio(struct request *req, struct bio *bio)
 	if (unlikely(bio_barrier(bio)))
 		req->flags |= (REQ_HARDBARRIER | REQ_NOMERGE);
 
+	if (bio_sync(bio))
+		req->flags |= REQ_RW_SYNC;
+
 	req->errors = 0;
 	req->hard_sector = req->sector = bio->bi_sector;
 	req->hard_nr_sectors = req->nr_sectors = bio_sectors(bio);
@@ -3346,12 +3365,11 @@ EXPORT_SYMBOL(end_that_request_chunk);
  */
 static void blk_done_softirq(struct softirq_action *h)
 {
-	struct list_head *cpu_list;
-	LIST_HEAD(local_list);
+	struct list_head *cpu_list, local_list;
 
 	local_irq_disable();
 	cpu_list = &__get_cpu_var(blk_cpu_done);
-	list_splice_init(cpu_list, &local_list);
+	list_replace_init(cpu_list, &local_list);
 	local_irq_enable();
 
 	while (!list_empty(&local_list)) {
@@ -3385,7 +3403,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
 }
 
 
-static struct notifier_block __devinitdata blk_cpu_notifier = {
+static struct notifier_block blk_cpu_notifier = {
 	.notifier_call	= blk_cpu_notify,
 };
 
@@ -3439,7 +3457,12 @@ void end_that_request_last(struct request *req, int uptodate)
 	if (unlikely(laptop_mode) && blk_fs_request(req))
 		laptop_io_completion();
 
-	if (disk && blk_fs_request(req)) {
+	/*
+	 * Account IO completion.  bar_rq isn't accounted as a normal
+	 * IO on queueing nor completion.  Accounting the containing
+	 * request is enough.
+	 */
+	if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
 		unsigned long duration = jiffies - req->start_time;
 		const int rw = rq_data_dir(req);